Apparatus for obtaining light metals by electrolysis



E. STEINBUCH ETAL 1,820,844

APPARATUS FOR OBTAINING LIGHT IETALS BY ELECTROLYSIS Filed Oct. 14, 1929 nm ac um wbn Uiu nJ I Q Z w .Ww 1L).

Patented Aug. 2 5, 1931' f UNITEDJV'STATE'S EWALD srEI Buo'H, or BASEL, AND GOTTFRIED'FI'TLLEMANN, or MONTHEY, vALAIs,

I SWITZERLAND, ASSIGNORS TO THE FIRM BASLE, OF BASEL, SWITZERLAND rATE SOCIETY Q11 CHEMICAL INDUSTRY IN APPARATUS FOR OBTAINING LIGHT METALS BY vELnc'raoLYsIs v I jApplication filed October 14, 1e29, Serial a...

The present invention relates to obtaining light metals by electrolysis of the molten haloid compounds in which the light metal rises to the surface of the molten electrolyte. As'an example, the electrolysis of fused common salt can be mentioned, but we do not wish the invention to be limited to obtaining the metal sodium.

The apparatus for obtaining this metal electrolytically can be divided generally into two groups; on the one hand, those in which the separated met-a1 is collected apart from the cathode (see for example, United States Patent N 0. 1,0"? hand, those'in which the separated metal itself acts as cathode or is conductingly connected with the cathode ,(see, for example, British Patent No. 357 5 of 1913, or United States Patent No. 1,092,178).

w The present invention consists in 'an apparatus of the last mentioned group. It has the advantage that it allows units of very large capacity to be constructed, which operatefat low Voltage and, by the prevention to a large extent of the formation of-the dis- 'turbing -metallic clouds in the ,electrolyte, enable very good current-outputs to be obtained. The essential feature of the invention consists in a particularconstruction of the" czlthode compartments of electrolytic cells. According to the invention, for the purpose ofcollecti-ng the light metal, ametallic body is provided, having suitably insulated'walls, which is immersed from above in the fused salt. This body is/channel' formed in section, extending longitudinally but of smg ll breadth, and is in. conducting connection with a working cathode which is immersed relatively deeply in the electrolyte and extends below the channel shaped-body parallel to its longitudinal direction.

The accompanying drawings represent an example suitable for carrying out the principle of thein'vention, but we do not wish 'to limit the'invention to the particular example shown.

Fig. I represents a cross-section through,

an electrolytic cell. a

Fig. II is a longitudinal section. Fig. III shows a particular form of the cathode which consists 4,988) and, on the other 399,637, and in Switzerland August 23, 1929.

of two pieces placed side by side. I i

1 is a furnace comprising, walls of refractory bricks or of reinforced concrete and provided with suitable lining, the walls being held together by suitable means, for example an iron casing '2; in the interior is a hollow spaceB of, for example, rectangular cross-section. I f

' Accordingto the invention, the iron body 4 is inserted in the upper part of the furnace. Below this is the cathode 5 also of iron. For the purpose of collecting the light metal rising along the working cathode, the body t is provided with one or more channels 6 which in the construction shown slope u wardson one side and in. which the collected light metal is led to a discharge tube 7., 8 is a lead for the electric current. The side walls of the body 4 are suitably insulated, for example, by plates 9 and 10 of asbestos for example,

cement fitting tightlyin the front-walls of the furnace, between which there is a hollow space in whichflat air cooled iron tubes 11 are placed. Longitudinal strips 12, "either con tinuous or divided into sections, press the plates together and are themselves pressed by transverse-strips 13 against the walls of I the furnace. The furnace contains, as usual, carbon anodes 14. These can be inserted, as in the, example illustrated, from above, or from below, or from the sides. In

NT 'oFFice] any case care is taken to provide a suitable space for collecting the'canode gas, either as in the figures by applying covers 15 in which the anodes are tightly inserted, or by collecting bells which are independent of the rest of the construction. If necessary, wirev gauzes serving'as diaphragms/such as described in United States Patent No. 1,074,- 988, can be provided between 5 and 14.

In the example shown, the body 4 and the cathode '5 are cast in'one piece, the current being'led to the working cathode through the body 4. As previouslystated, we do not wish, however, to limit ourselves to the construction' shown. The parts 4 and 5. can also'consist of separate members and the cur-. rent can be led to 5 independently of 4;

lead passing through the collected light metal may be brought to the cathode. Also, in respect to the form of the body 4, and the section of one or more longitudinal channels, and to the insulation of its outer walls, we do not wish to restrict ourselves to the example shown. Instead ,of a single collecting body with the cathode below it, sevcral of such conbinations can obviously be provided in an electrolytic cell. -The working cathode can consist of several, for example as shown in Fig. III, pieces placed side by side; it can further be corrugated, incised, or perforated. The channel need not slope upwards to one side, as shown in Fig. II, it could further slope upwards from the centre to both sides in order .to lead the separated metal to both front sides of the electrolytic apparatus, or, conversely, it might ascend from both sides towards the centre, in which case the metal would be drawn offv laterally, for example, from the centre of the furnace. In short, we claim all modifications in which the formation of the particular cathode compartment, as explained, isadaptable in the construction of electrolytic cells. I

What we claim is i I I 1. In electrolytic cells for obtaining light metals by electrolysis of fused haloid salts,

the arrangement wherein the cathode compartments comprise, for the purpose of collecting the light metal, a relatively narrow but elongated metallic body provided with suitably insulated walls, immersed in the upper part of the fused salt, provided with a longitudinallyextending channel and conductively connected with the working cathode, the latter being'immersed below said. body in the deeper parts of the electrolyte and extending parallel to said channel in the longitudinal direction thereof.

' 2. In electrolytic cells for obtaining light metals by electrolysis of fused haloid salts, the arrangement wherein the cathode coinpartments comprise, for the purpose of collecting the light metal, a relatively narrow but elongated metallic body provided with suitably insulated walls, immersed in the upper part of the fused salt, provided with a plurality of longitudinally extending channels and conductively connected with' the working cathode, the latter being-immersed below said body in the deeper parts of the electrolyte and extending parallel suitably insulated walls, immersed in the upper part of the fused salt, provided with at least one longitudinally extended sloping collecting channel and conductively COH'.

nected with the working cathode, the latter being immersed below said body in. the deeper parts of the electrolyte and extending parallel to said channel in the longitudinal direction thereof.

5. In electrolytic cells for obtainin light metals by electrolysis of fused haloi salts, the arrangement wherein the cathode compartments comprise, for the purpose of collecting the light 'metal, a relatively narrow but elongated metallic body provided with suitably insulated walls, immersed in the upper part of the fused salt, provided with a longitudinally extending channel and conductively connected with the working cathode, the latter consisting of several )ieces immersed below said body in the eeper parts of the electrolyte and extending parallel to said channel in the longitudinal direction thereof. 1

In witness whereof we have hereunto signed our names this 27th-day of September, 1929.

' EWALD STEINBUCH.

GOTTFRIED FULLEMANN.

to said channel in the longitudinal direc tion thereof.

3. In electrolytic cells for obtaining light metals by electrolysis of fused haloid salts, the arrangement wherein the cathode compartments comprise, for the purpose of collecting the light metal, a relatively narrow but elongated metallic'body provided 'with suitably insulated walls, immersed in the upper part of the fused salt, provided with 

